Colour calibration is important, particularly for displays. Instruments to do this can be costly, but even a more basic method is a big help.
colour cognition
This explains how OS X renders an image for output, to the display, printer, etc., and what rendering intent is.
Explaining colour management for the non-pro user. Why do you need it?
Should all displays use Apple’s True Tone automatic white balance adjustment?
Semantic primes represent “the complete inventory of simple universal concepts that are embedded in the lexicons of all (or most) human languages.” Do they suffice?
How pigments work, and some of their practical problems.
Chroma is hard to separate from lightness. An important painting point is that mixing paints cannot increase chroma. Instead it tends to reduce it towards muddy grey.
Although lightness and chroma can usually be approached successfully using methodical approaches, long experience has shown that hue is much more hit or miss. Developing a good ‘eye’ for colours is generally much more important.
Lightness is key to the depiction of materials, textures, edges, and form. Illusions can confound the viewer, and it is vital to map the lightness of your motif to that of your painting.
What do we actually perceive of colour?
The Eclectic Light Company 